Justina is a fifteen years old girl who lives with her mother and stepfather in Mexico City. In her sexual-awakening, she starts flirting with the only man in her life, her stepfather, causing the accidental murder of her mother and stepfather. Shocked, she runs away from home, crazy, just dressed with her nightgown. Ivan, a police detective who practices torture as daily routine and is reduced to the rank of street cop, looks for her all night long.